The packaging of fresh roasted coffee exhibiting improved aroma retention and freshness throughout the package's useful life is disclosed in commonly assigned allowed U.S. patent application Ser. No. 07/358,927 filed on May 26, 1989 in the names of Peter J. Hargraves, Robert S. Dirksing and Theodore P. Merz, now U.S. Pat. No. 4,966,780 issued on Oct. 30, 1990, the disclosure of said Application being hereby incorporated herein by reference.
The aforementioned commonly assigned U.S. patent application, now U.S. Pat. No. 4,966,780, teaches the packaging of roasted coffee as quickly as feasible after the roasting process has been performed in a semi-rigid, substantially gas-impervious polymeric container capable of withstanding the pressure generated by the release of carbon dioxide and other gases from the fresh roasted coffee in the container. A porous filter member is preferably secured across the discharge orifice of the container to prevent coffee from aspirating from the container when the pressurized package is initially opened by the consumer. The filter is normally removed and discarded after initial opening of the package.
The semi-rigid container employs resealable closure means which are capable of:
1. Providing a substantially gas-tight seal to the atmosphere prior to initial opening by the consumer; and
2. Establishing a reseal which is effective to resist ambient atmospheric pressure changes.
As used both herein and in the aforementioned commonly assigned U.S. patent application, now U.S. Pat. No. 4,966,780, a reseal which is "effective to substantially resist ambient atmospheric pressure changes" is defined as one which will produce an oxygen content in the package of roasted coffee which is at least about ten (10) percent lower than the oxygen content of the surrounding ambient atmosphere, as measured two days after the package has been initially opened, the closure member and filter removed for a period of about thirty seconds without removing any coffee from the package, and only the closure member thereafter snugly reapplied. The establishment of such an effective reseal minimizes the ingress of atmospheric oxygen into the package of roasted coffee intermediate dispensing cycles after the package has been initially opened.
In a particularly preferred embodiment of the package disclosed in the aforementioned commonly assigned U.S. patent application, now U.S. Pat. No. 4,966,780, the filter used to prevent aspiration of the pressurized coffee from the discharge orifice of the container upon initial opening by the consumer comprises a porous filter secured by a filter support member across the discharge orifice of the container. The substantially gas-tight seal to the atmosphere is initially established in the package by means of the opposed surfaces of the filter support member. One surface of the filter support member establishes a seal with the discharge orifice of the container while the opposed surface of the filter support member establishes a seal with the innermost surface of the closure.
The means for securing the resealable closure onto the semi-rigid container preferably comprises complementary thread sets which include at least one gas vent to permit escape of the pressurized gas from the interior of the container before the threads become completely disengaged from one another. This prevents missiling of the closure from the container upon initial opening of the pressurized package.
Upon initial opening of the package, the filter support member and filter are normally removed and discarded so the reseal which is to be effective in resisting ambient atmospheric pressure changes must thereafter be established directly between the innermost surface of the closure and the discharge orifice of the container.
While the magnitude of the torque which must be applied to establish such a reseal directly between the closure and the container will normally depend upon such factors as the discharge orifice and closure configuration as well as their materials of construction, establishment of a reseal which is effective to substantially resist ambient atmospheric pressure changes can normally be made more certain by tightening the closure as far as the consumer's strength will permit. However, it is normally not necessary to retighten the closure as far as the consumer's strength will permit in order to establish a reseal which is effective to substantially resist ambient atmospheric pressure changes. Furthermore, such extreme retightening of the closure by one user may make it all but impossible for the next user in the same household to remove the closure and dispense product from the container, particularly if the second user is of lesser strength than the first user. Such disparities in strength are common among different members of a single household, all of whom are likely to use the same package.